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db6da75556
freebsd/usr.sbin/inetd/inetd.c
Sheldon Hearn db6da75556 Remove unnecessary macro introduced in previous commit. 
Also, the previous commit failed to reference:

PR:	12731
Submitted by:	dwmalone@maths.tcd.ie (David "Inetd" Malone)
1999-07-22 16:10:40 +00:00

1663 lines
41 KiB
C
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/*
* Copyright (c) 1983, 1991, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1983, 1991, 1993, 1994\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)from: inetd.c 8.4 (Berkeley) 4/13/94";
#endif
static const char rcsid[] =
"$Id: inetd.c,v 1.66 1999/07/22 15:57:37 sheldonh Exp $";
#endif /* not lint */
/*
* Inetd - Internet super-server
*
* This program invokes all internet services as needed. Connection-oriented
* services are invoked each time a connection is made, by creating a process.
* This process is passed the connection as file descriptor 0 and is expected
* to do a getpeername to find out the source host and port.
*
* Datagram oriented services are invoked when a datagram
* arrives; a process is created and passed a pending message
* on file descriptor 0. Datagram servers may either connect
* to their peer, freeing up the original socket for inetd
* to receive further messages on, or ``take over the socket'',
* processing all arriving datagrams and, eventually, timing
* out. The first type of server is said to be ``multi-threaded'';
* the second type of server ``single-threaded''.
*
* Inetd uses a configuration file which is read at startup
* and, possibly, at some later time in response to a hangup signal.
* The configuration file is ``free format'' with fields given in the
* order shown below. Continuation lines for an entry must being with
* a space or tab. All fields must be present in each entry.
*
* service name must be in /etc/services or must
* name a tcpmux service
* socket type stream/dgram/raw/rdm/seqpacket
* protocol must be in /etc/protocols
* wait/nowait single-threaded/multi-threaded
* user user to run daemon as
* server program full path name
* server program arguments maximum of MAXARGS (20)
*
* TCP services without official port numbers are handled with the
* RFC1078-based tcpmux internal service. Tcpmux listens on port 1 for
* requests. When a connection is made from a foreign host, the service
* requested is passed to tcpmux, which looks it up in the servtab list
* and returns the proper entry for the service. Tcpmux returns a
* negative reply if the service doesn't exist, otherwise the invoked
* server is expected to return the positive reply if the service type in
* inetd.conf file has the prefix "tcpmux/". If the service type has the
* prefix "tcpmux/+", tcpmux will return the positive reply for the
* process; this is for compatibility with older server code, and also
* allows you to invoke programs that use stdin/stdout without putting any
* special server code in them. Services that use tcpmux are "nowait"
* because they do not have a well-known port and hence cannot listen
* for new requests.
*
* For RPC services
* service name/version must be in /etc/rpc
* socket type stream/dgram/raw/rdm/seqpacket
* protocol must be in /etc/protocols
* wait/nowait single-threaded/multi-threaded
* user user to run daemon as
* server program full path name
* server program arguments maximum of MAXARGS
*
* Comment lines are indicated by a `#' in column 1.
*/
#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/wait.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <arpa/inet.h>
#include <rpc/rpc.h>
#include <rpc/pmap_clnt.h>
#include <errno.h>
#include <err.h>
#include <fcntl.h>
#include <grp.h>
#include <netdb.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <tcpd.h>
#include <unistd.h>
#include <libutil.h>
#include <sysexits.h>
#include "inetd.h"
#include "pathnames.h"
#ifndef LIBWRAP_ALLOW_FACILITY
# define LIBWRAP_ALLOW_FACILITY LOG_AUTH
#endif
#ifndef LIBWRAP_ALLOW_SEVERITY
# define LIBWRAP_ALLOW_SEVERITY LOG_INFO
#endif
#ifndef LIBWRAP_DENY_FACILITY
# define LIBWRAP_DENY_FACILITY LOG_AUTH
#endif
#ifndef LIBWRAP_DENY_SEVERITY
# define LIBWRAP_DENY_SEVERITY LOG_WARNING
#endif
#define ISWRAP(sep) \
( ((wrap_ex && !(sep)->se_bi) || (wrap_bi && (sep)->se_bi)) \
&& ( ((sep)->se_accept && (sep)->se_socktype == SOCK_STREAM) \
|| (sep)->se_socktype == SOCK_DGRAM))
#ifdef LOGIN_CAP
#include <login_cap.h>
/* see init.c */
#define RESOURCE_RC "daemon"
#endif
#ifndef MAXCHILD
#define MAXCHILD -1 /* maximum number of this service
< 0 = no limit */
#endif
#ifndef MAXCPM
#define MAXCPM -1 /* rate limit invocations from a
single remote address,
< 0 = no limit */
#endif
#define TOOMANY 256 /* don't start more than TOOMANY */
#define CNT_INTVL 60 /* servers in CNT_INTVL sec. */
#define RETRYTIME (60*10) /* retry after bind or server fail */
#define MAX_MAXCHLD 32767 /* max allowable max children */
#define SIGBLOCK (sigmask(SIGCHLD)|sigmask(SIGHUP)|sigmask(SIGALRM))
int allow_severity;
int deny_severity;
int wrap_ex = 0;
int wrap_bi = 0;
int debug = 0;
int log = 0;
int nsock;
int maxsock; /* highest-numbered descriptor */
fd_set allsock;
int options;
int timingout;
int toomany = TOOMANY;
int maxchild = MAXCHILD;
int maxcpm = MAXCPM;
struct servent *sp;
struct rpcent *rpc;
struct in_addr bind_address;
int signalpipe[2];
struct servtab *servtab;
extern struct biltin biltins[];
#define NUMINT (sizeof(intab) / sizeof(struct inent))
char *CONFIG = _PATH_INETDCONF;
char *pid_file = _PATH_INETDPID;
#ifdef OLD_SETPROCTITLE
char **Argv;
char *LastArg;
#endif
int
getvalue(arg, value, whine)
char *arg, *whine;
int *value;
{
int tmp;
char *p;
tmp = strtol(arg, &p, 0);
if (tmp < 1 || *p) {
syslog(LOG_ERR, whine, arg);
return 1; /* failure */
}
*value = tmp;
return 0; /* success */
}
int
main(argc, argv, envp)
int argc;
char *argv[], *envp[];
{
struct servtab *sep;
struct passwd *pwd;
struct group *grp;
struct sigaction sa, saalrm, sachld, sahup, sapipe;
int tmpint, ch, dofork;
pid_t pid;
char buf[50];
#ifdef LOGIN_CAP
login_cap_t *lc = NULL;
#endif
struct request_info req;
int denied;
char *service = NULL;
char *pnm;
struct sockaddr_in peer;
int i;
#ifdef OLD_SETPROCTITLE
Argv = argv;
if (envp == 0 || *envp == 0)
envp = argv;
while (*envp)
envp++;
LastArg = envp[-1] + strlen(envp[-1]);
#endif
openlog("inetd", LOG_PID | LOG_NOWAIT, LOG_DAEMON);
bind_address.s_addr = htonl(INADDR_ANY);
while ((ch = getopt(argc, argv, "dlwWR:a:c:C:p:")) != -1)
switch(ch) {
case 'd':
debug = 1;
options |= SO_DEBUG;
break;
case 'l':
log = 1;
break;
case 'R':
getvalue(optarg, &toomany,
"-R %s: bad value for service invocation rate");
break;
case 'c':
getvalue(optarg, &maxchild,
"-c %s: bad value for maximum children");
break;
case 'C':
getvalue(optarg, &maxcpm,
"-C %s: bad value for maximum children/minute");
break;
case 'a':
if (!inet_aton(optarg, &bind_address)) {
syslog(LOG_ERR,
"-a %s: invalid IP address", optarg);
exit(EX_USAGE);
}
break;
case 'p':
pid_file = optarg;
break;
case 'w':
wrap_ex++;
break;
case 'W':
wrap_bi++;
break;
case '?':
default:
syslog(LOG_ERR,
"usage: inetd [-dlwW] [-a address] [-R rate]"
" [-c maximum] [-C rate]"
" [-p pidfile] [conf-file]");
exit(EX_USAGE);
}
argc -= optind;
argv += optind;
if (argc > 0)
CONFIG = argv[0];
if (debug == 0) {
FILE *fp;
if (daemon(0, 0) < 0) {
syslog(LOG_WARNING, "daemon(0,0) failed: %m");
}
/*
* In case somebody has started inetd manually, we need to
* clear the logname, so that old servers run as root do not
* get the user's logname..
*/
if (setlogin("") < 0) {
syslog(LOG_WARNING, "cannot clear logname: %m");
/* no big deal if it fails.. */
}
pid = getpid();
fp = fopen(pid_file, "w");
if (fp) {
fprintf(fp, "%ld\n", (long)pid);
fclose(fp);
} else {
syslog(LOG_WARNING, "%s: %m", pid_file);
}
}
sa.sa_flags = 0;
sigemptyset(&sa.sa_mask);
sigaddset(&sa.sa_mask, SIGALRM);
sigaddset(&sa.sa_mask, SIGCHLD);
sigaddset(&sa.sa_mask, SIGHUP);
sa.sa_handler = flag_retry;
sigaction(SIGALRM, &sa, &saalrm);
config();
sa.sa_handler = flag_config;
sigaction(SIGHUP, &sa, &sahup);
sa.sa_handler = flag_reapchild;
sigaction(SIGCHLD, &sa, &sachld);
sa.sa_handler = SIG_IGN;
sigaction(SIGPIPE, &sa, &sapipe);
{
/* space for daemons to overwrite environment for ps */
#define DUMMYSIZE 100
char dummy[DUMMYSIZE];
(void)memset(dummy, 'x', DUMMYSIZE - 1);
dummy[DUMMYSIZE - 1] = '\0';
(void)setenv("inetd_dummy", dummy, 1);
}
if (pipe(signalpipe) != 0) {
syslog(LOG_ERR, "pipe: %%m");
exit(EX_OSERR);
}
FD_SET(signalpipe[0], &allsock);
nsock++;
if (signalpipe[0] > maxsock)
maxsock = signalpipe[0];
if (signalpipe[1] > maxsock)
maxsock = signalpipe[1];
for (;;) {
int n, ctrl;
fd_set readable;
if (nsock == 0) {
syslog(LOG_ERR, "%s: nsock=0", __FUNCTION__);
exit(EX_SOFTWARE);
}
readable = allsock;
if ((n = select(maxsock + 1, &readable, (fd_set *)0,
(fd_set *)0, (struct timeval *)0)) <= 0) {
if (n < 0 && errno != EINTR) {
syslog(LOG_WARNING, "select: %m");
sleep(1);
}
continue;
}
/* handle any queued signal flags */
if (FD_ISSET(signalpipe[0], &readable)) {
int n;
if (ioctl(signalpipe[0], FIONREAD, &n) != 0) {
syslog(LOG_ERR, "ioctl: %m");
exit(EX_OSERR);
}
while (--n >= 0) {
char c;
if (read(signalpipe[0], &c, 1) != 1) {
syslog(LOG_ERR, "read: %m");
exit(EX_OSERR);
}
if (debug)
warnx("Handling signal flag %c", c);
switch(c) {
case 'A': /* sigalrm */
retry();
break;
case 'C': /* sigchld */
reapchild();
break;
case 'H': /* sighup */
config();
break;
}
}
}
for (sep = servtab; n && sep; sep = sep->se_next)
if (sep->se_fd != -1 && FD_ISSET(sep->se_fd, &readable)) {
n--;
if (debug)
warnx("someone wants %s", sep->se_service);
if (sep->se_accept && sep->se_socktype == SOCK_STREAM) {
ctrl = accept(sep->se_fd, (struct sockaddr *)0,
(int *)0);
if (debug)
warnx("accept, ctrl %d", ctrl);
if (ctrl < 0) {
if (errno != EINTR)
syslog(LOG_WARNING,
"accept (for %s): %m",
sep->se_service);
if (sep->se_accept &&
sep->se_socktype == SOCK_STREAM)
close(ctrl);
continue;
}
if (cpmip(sep, ctrl) < 0) {
close(ctrl);
continue;
}
} else
ctrl = sep->se_fd;
if (log && !ISWRAP(sep)) {
pnm = "unknown";
i = sizeof peer;
if (getpeername(ctrl, (struct sockaddr *)
&peer, &i)) {
i = sizeof peer;
if (recvfrom(ctrl, buf, sizeof(buf),
MSG_PEEK,
(struct sockaddr *)&peer, &i) >= 0)
pnm = inet_ntoa(peer.sin_addr);
}
else
pnm = inet_ntoa(peer.sin_addr);
syslog(LOG_INFO,"%s from %s", sep->se_service, pnm);
}
(void) sigblock(SIGBLOCK);
pid = 0;
/*
* Fork for all external services, builtins which need to
* fork and anything we're wrapping (as wrapping might
* block or use hosts_options(5) twist).
*/
dofork = !sep->se_bi || sep->se_bi->bi_fork || ISWRAP(sep);
if (dofork) {
if (sep->se_count++ == 0)
(void)gettimeofday(&sep->se_time, (struct timezone *)NULL);
else if (sep->se_count >= toomany) {
struct timeval now;
(void)gettimeofday(&now, (struct timezone *)NULL);
if (now.tv_sec - sep->se_time.tv_sec >
CNT_INTVL) {
sep->se_time = now;
sep->se_count = 1;
} else {
syslog(LOG_ERR,
"%s/%s server failing (looping), service terminated",
sep->se_service, sep->se_proto);
close_sep(sep);
sigsetmask(0L);
if (!timingout) {
timingout = 1;
alarm(RETRYTIME);
}
continue;
}
}
pid = fork();
}
if (pid < 0) {
syslog(LOG_ERR, "fork: %m");
if (sep->se_accept &&
sep->se_socktype == SOCK_STREAM)
close(ctrl);
sigsetmask(0L);
sleep(1);
continue;
}
if (pid)
addchild(sep, pid);
sigsetmask(0L);
if (pid == 0) {
if (dofork) {
if (debug)
warnx("+ closing from %d", maxsock);
for (tmpint = maxsock; tmpint > 2; tmpint--)
if (tmpint != ctrl)
(void) close(tmpint);
sigaction(SIGALRM, &saalrm, (struct sigaction *)0);
sigaction(SIGCHLD, &sachld, (struct sigaction *)0);
sigaction(SIGHUP, &sahup, (struct sigaction *)0);
/* SIGPIPE reset before exec */
}
/*
* Call tcpmux to find the real service to exec.
*/
if (sep->se_bi &&
sep->se_bi->bi_fn == (void (*)()) tcpmux) {
sep = tcpmux(ctrl);
if (sep == NULL) {
close(ctrl);
_exit(0);
}
}
if (ISWRAP(sep)) {
inetd_setproctitle("wrapping", ctrl);
service = sep->se_server_name ?
sep->se_server_name : sep->se_service;
request_init(&req, RQ_DAEMON, service, RQ_FILE, ctrl, NULL);
fromhost(&req);
deny_severity = LIBWRAP_DENY_FACILITY|LIBWRAP_DENY_SEVERITY;
allow_severity = LIBWRAP_ALLOW_FACILITY|LIBWRAP_ALLOW_SEVERITY;
denied = !hosts_access(&req);
if (denied) {
syslog(deny_severity,
"refused connection from %.500s, service %s (%s)",
eval_client(&req), service, sep->se_proto);
if (sep->se_socktype != SOCK_STREAM)
recv(ctrl, buf, sizeof (buf), 0);
if (dofork)
_exit(0);
}
if (log) {
syslog(allow_severity,
"connection from %.500s, service %s (%s)",
eval_client(&req), service, sep->se_proto);
}
}
if (sep->se_bi) {
(*sep->se_bi->bi_fn)(ctrl, sep);
} else {
if (debug)
warnx("%d execl %s",
getpid(), sep->se_server);
dup2(ctrl, 0);
close(ctrl);
dup2(0, 1);
dup2(0, 2);
if ((pwd = getpwnam(sep->se_user)) == NULL) {
syslog(LOG_ERR,
"%s/%s: %s: No such user",
sep->se_service, sep->se_proto,
sep->se_user);
if (sep->se_socktype != SOCK_STREAM)
recv(0, buf, sizeof (buf), 0);
_exit(EX_NOUSER);
}
grp = NULL;
if ( sep->se_group != NULL
&& (grp = getgrnam(sep->se_group)) == NULL
) {
syslog(LOG_ERR,
"%s/%s: %s: No such group",
sep->se_service, sep->se_proto,
sep->se_group);
if (sep->se_socktype != SOCK_STREAM)
recv(0, buf, sizeof (buf), 0);
_exit(EX_NOUSER);
}
if (grp != NULL)
pwd->pw_gid = grp->gr_gid;
#ifdef LOGIN_CAP
if ((lc = login_getclass(sep->se_class)) == NULL) {
/* error syslogged by getclass */
syslog(LOG_ERR,
"%s/%s: %s: login class error",
sep->se_service, sep->se_proto,
sep->se_class);
if (sep->se_socktype != SOCK_STREAM)
recv(0, buf, sizeof (buf), 0);
_exit(EX_NOUSER);
}
#endif
if (setsid() < 0) {
syslog(LOG_ERR,
"%s: can't setsid(): %m",
sep->se_service);
/* _exit(EX_OSERR); not fatal yet */
}
#ifdef LOGIN_CAP
if (setusercontext(lc, pwd, pwd->pw_uid,
LOGIN_SETALL) != 0) {
syslog(LOG_ERR,
"%s: can't setusercontext(..%s..): %m",
sep->se_service, sep->se_user);
_exit(EX_OSERR);
}
#else
if (pwd->pw_uid) {
if (setlogin(sep->se_user) < 0) {
syslog(LOG_ERR,
"%s: can't setlogin(%s): %m",
sep->se_service, sep->se_user);
/* _exit(EX_OSERR); not yet */
}
if (setgid(pwd->pw_gid) < 0) {
syslog(LOG_ERR,
"%s: can't set gid %d: %m",
sep->se_service, pwd->pw_gid);
_exit(EX_OSERR);
}
(void) initgroups(pwd->pw_name,
pwd->pw_gid);
if (setuid(pwd->pw_uid) < 0) {
syslog(LOG_ERR,
"%s: can't set uid %d: %m",
sep->se_service, pwd->pw_uid);
_exit(EX_OSERR);
}
}
#endif
sigaction(SIGPIPE, &sapipe,
(struct sigaction *)0);
execv(sep->se_server, sep->se_argv);
syslog(LOG_ERR,
"cannot execute %s: %m", sep->se_server);
if (sep->se_socktype != SOCK_STREAM)
recv(0, buf, sizeof (buf), 0);
}
if (dofork)
_exit(0);
}
if (sep->se_accept && sep->se_socktype == SOCK_STREAM)
close(ctrl);
}
}
}
/*
* Add a signal flag to the signal flag queue for later handling
*/
void flag_signal(c)
char c;
{
if (write(signalpipe[1], &c, 1) != 1) {
syslog(LOG_ERR, "write: %m");
_exit(EX_OSERR);
}
}
/*
* Record a new child pid for this service. If we've reached the
* limit on children, then stop accepting incoming requests.
*/
void
addchild(struct servtab *sep, pid_t pid)
{
#ifdef SANITY_CHECK
if (sep->se_numchild >= sep->se_maxchild) {
syslog(LOG_ERR, "%s: %d >= %d",
__FUNCTION__, sep->se_numchild, sep->se_maxchild);
exit(EX_SOFTWARE);
}
#endif
if (sep->se_maxchild == 0)
return;
sep->se_pids[sep->se_numchild++] = pid;
if (sep->se_numchild == sep->se_maxchild)
disable(sep);
}
/*
* Some child process has exited. See if it's on somebody's list.
*/
void
flag_reapchild(signo)
int signo;
{
flag_signal('C');
}
void
reapchild()
{
int k, status;
pid_t pid;
struct servtab *sep;
for (;;) {
pid = wait3(&status, WNOHANG, (struct rusage *)0);
if (pid <= 0)
break;
if (debug)
warnx("%d reaped, status %#x", pid, status);
for (sep = servtab; sep; sep = sep->se_next) {
for (k = 0; k < sep->se_numchild; k++)
if (sep->se_pids[k] == pid)
break;
if (k == sep->se_numchild)
continue;
if (sep->se_numchild == sep->se_maxchild)
enable(sep);
sep->se_pids[k] = sep->se_pids[--sep->se_numchild];
if (status)
syslog(LOG_WARNING,
"%s[%d]: exit status 0x%x",
sep->se_server, pid, status);
break;
}
}
}
void
flag_config(signo)
int signo;
{
flag_signal('H');
}
void config()
{
struct servtab *sep, *new, **sepp;
long omask;
if (!setconfig()) {
syslog(LOG_ERR, "%s: %m", CONFIG);
return;
}
for (sep = servtab; sep; sep = sep->se_next)
sep->se_checked = 0;
while ((new = getconfigent())) {
if (getpwnam(new->se_user) == NULL) {
syslog(LOG_ERR,
"%s/%s: No such user '%s', service ignored",
new->se_service, new->se_proto, new->se_user);
continue;
}
if (new->se_group && getgrnam(new->se_group) == NULL) {
syslog(LOG_ERR,
"%s/%s: No such group '%s', service ignored",
new->se_service, new->se_proto, new->se_group);
continue;
}
#ifdef LOGIN_CAP
if (login_getclass(new->se_class) == NULL) {
/* error syslogged by getclass */
syslog(LOG_ERR,
"%s/%s: %s: login class error, service ignored",
new->se_service, new->se_proto, new->se_class);
continue;
}
#endif
for (sep = servtab; sep; sep = sep->se_next)
if (strcmp(sep->se_service, new->se_service) == 0 &&
strcmp(sep->se_proto, new->se_proto) == 0)
break;
if (sep != 0) {
int i;
#define SWAP(a, b) { typeof(a) c = a; a = b; b = c; }
omask = sigblock(SIGBLOCK);
/* copy over outstanding child pids */
if (sep->se_maxchild && new->se_maxchild) {
new->se_numchild = sep->se_numchild;
if (new->se_numchild > new->se_maxchild)
new->se_numchild = new->se_maxchild;
memcpy(new->se_pids, sep->se_pids,
new->se_numchild * sizeof(*new->se_pids));
}
SWAP(sep->se_pids, new->se_pids);
sep->se_maxchild = new->se_maxchild;
sep->se_numchild = new->se_numchild;
sep->se_maxcpm = new->se_maxcpm;
/* might need to turn on or off service now */
if (sep->se_fd >= 0) {
if (sep->se_maxchild
&& sep->se_numchild == sep->se_maxchild) {
if (FD_ISSET(sep->se_fd, &allsock))
disable(sep);
} else {
if (!FD_ISSET(sep->se_fd, &allsock))
enable(sep);
}
}
sep->se_accept = new->se_accept;
SWAP(sep->se_user, new->se_user);
SWAP(sep->se_group, new->se_group);
#ifdef LOGIN_CAP
SWAP(sep->se_class, new->se_class);
#endif
SWAP(sep->se_server, new->se_server);
SWAP(sep->se_server_name, new->se_server_name);
for (i = 0; i < MAXARGV; i++)
SWAP(sep->se_argv[i], new->se_argv[i]);
sigsetmask(omask);
freeconfig(new);
if (debug)
print_service("REDO", sep);
} else {
sep = enter(new);
if (debug)
print_service("ADD ", sep);
}
sep->se_checked = 1;
if (ISMUX(sep)) {
sep->se_fd = -1;
continue;
}
if (!sep->se_rpc) {
sp = getservbyname(sep->se_service, sep->se_proto);
if (sp == 0) {
syslog(LOG_ERR, "%s/%s: unknown service",
sep->se_service, sep->se_proto);
sep->se_checked = 0;
continue;
}
if (sp->s_port != sep->se_ctrladdr.sin_port) {
sep->se_ctrladdr.sin_family = AF_INET;
sep->se_ctrladdr.sin_addr = bind_address;
sep->se_ctrladdr.sin_port = sp->s_port;
if (sep->se_fd >= 0)
close_sep(sep);
}
} else {
rpc = getrpcbyname(sep->se_service);
if (rpc == 0) {
syslog(LOG_ERR, "%s/%s unknown RPC service.",
sep->se_service, sep->se_proto);
if (sep->se_fd != -1)
(void) close(sep->se_fd);
sep->se_fd = -1;
continue;
}
if (rpc->r_number != sep->se_rpc_prog) {
if (sep->se_rpc_prog)
unregisterrpc(sep);
sep->se_rpc_prog = rpc->r_number;
if (sep->se_fd != -1)
(void) close(sep->se_fd);
sep->se_fd = -1;
}
}
if (sep->se_fd == -1)
setup(sep);
}
endconfig();
/*
* Purge anything not looked at above.
*/
omask = sigblock(SIGBLOCK);
sepp = &servtab;
while ((sep = *sepp)) {
if (sep->se_checked) {
sepp = &sep->se_next;
continue;
}
*sepp = sep->se_next;
if (sep->se_fd >= 0)
close_sep(sep);
if (debug)
print_service("FREE", sep);
if (sep->se_rpc && sep->se_rpc_prog > 0)
unregisterrpc(sep);
freeconfig(sep);
free((char *)sep);
}
(void) sigsetmask(omask);
}
void
unregisterrpc(sep)
struct servtab *sep;
{
int i;
struct servtab *sepp;
long omask;
omask = sigblock(SIGBLOCK);
for (sepp = servtab; sepp; sepp = sepp->se_next) {
if (sepp == sep)
continue;
if (sep->se_checked == 0 ||
!sepp->se_rpc ||
sep->se_rpc_prog != sepp->se_rpc_prog)
continue;
return;
}
if (debug)
print_service("UNREG", sep);
for (i = sep->se_rpc_lowvers; i <= sep->se_rpc_highvers; i++)
pmap_unset(sep->se_rpc_prog, i);
if (sep->se_fd != -1)
(void) close(sep->se_fd);
sep->se_fd = -1;
(void) sigsetmask(omask);
}
void
flag_retry(signo)
int signo;
{
flag_signal('A');
}
void
retry()
{
struct servtab *sep;
timingout = 0;
for (sep = servtab; sep; sep = sep->se_next)
if (sep->se_fd == -1 && !ISMUX(sep))
setup(sep);
}
void
setup(sep)
struct servtab *sep;
{
int on = 1;
if ((sep->se_fd = socket(AF_INET, sep->se_socktype, 0)) < 0) {
if (debug)
warn("socket failed on %s/%s",
sep->se_service, sep->se_proto);
syslog(LOG_ERR, "%s/%s: socket: %m",
sep->se_service, sep->se_proto);
return;
}
#define turnon(fd, opt) \
setsockopt(fd, SOL_SOCKET, opt, (char *)&on, sizeof (on))
if (strcmp(sep->se_proto, "tcp") == 0 && (options & SO_DEBUG) &&
turnon(sep->se_fd, SO_DEBUG) < 0)
syslog(LOG_ERR, "setsockopt (SO_DEBUG): %m");
if (turnon(sep->se_fd, SO_REUSEADDR) < 0)
syslog(LOG_ERR, "setsockopt (SO_REUSEADDR): %m");
#ifdef SO_PRIVSTATE
if (turnon(sep->se_fd, SO_PRIVSTATE) < 0)
syslog(LOG_ERR, "setsockopt (SO_PRIVSTATE): %m");
#endif
#undef turnon
if (sep->se_type == TTCP_TYPE)
if (setsockopt(sep->se_fd, IPPROTO_TCP, TCP_NOPUSH,
(char *)&on, sizeof (on)) < 0)
syslog(LOG_ERR, "setsockopt (TCP_NOPUSH): %m");
if (bind(sep->se_fd, (struct sockaddr *)&sep->se_ctrladdr,
sizeof (sep->se_ctrladdr)) < 0) {
if (debug)
warn("bind failed on %s/%s",
sep->se_service, sep->se_proto);
syslog(LOG_ERR, "%s/%s: bind: %m",
sep->se_service, sep->se_proto);
(void) close(sep->se_fd);
sep->se_fd = -1;
if (!timingout) {
timingout = 1;
alarm(RETRYTIME);
}
return;
}
if (sep->se_rpc) {
int i, len = sizeof(struct sockaddr);
if (getsockname(sep->se_fd,
(struct sockaddr*)&sep->se_ctrladdr, &len) < 0){
syslog(LOG_ERR, "%s/%s: getsockname: %m",
sep->se_service, sep->se_proto);
(void) close(sep->se_fd);
sep->se_fd = -1;
return;
}
if (debug)
print_service("REG ", sep);
for (i = sep->se_rpc_lowvers; i <= sep->se_rpc_highvers; i++) {
pmap_unset(sep->se_rpc_prog, i);
pmap_set(sep->se_rpc_prog, i,
(sep->se_socktype == SOCK_DGRAM)
? IPPROTO_UDP : IPPROTO_TCP,
ntohs(sep->se_ctrladdr.sin_port));
}
}
if (sep->se_socktype == SOCK_STREAM)
listen(sep->se_fd, 64);
enable(sep);
if (debug) {
warnx("registered %s on %d",
sep->se_server, sep->se_fd);
}
}
/*
* Finish with a service and its socket.
*/
void
close_sep(sep)
struct servtab *sep;
{
if (sep->se_fd >= 0) {
if (FD_ISSET(sep->se_fd, &allsock))
disable(sep);
(void) close(sep->se_fd);
sep->se_fd = -1;
}
sep->se_count = 0;
sep->se_numchild = 0; /* forget about any existing children */
}
int
matchservent(name1, name2, proto)
char *name1, *name2, *proto;
{
char **alias;
struct servent *se;
if ((se = getservbyname(name1, proto)) != NULL) {
if (strcmp(name2, se->s_name) == 0)
return(1);
for (alias = se->s_aliases; *alias; alias++)
if (strcmp(name2, *alias) == 0)
return(1);
}
return(0);
}
struct servtab *
enter(cp)
struct servtab *cp;
{
struct servtab *sep;
long omask;
sep = (struct servtab *)malloc(sizeof (*sep));
if (sep == (struct servtab *)0) {
syslog(LOG_ERR, "Out of memory.");
exit(EX_OSERR);
}
*sep = *cp;
sep->se_fd = -1;
omask = sigblock(SIGBLOCK);
sep->se_next = servtab;
servtab = sep;
sigsetmask(omask);
return (sep);
}
void
enable(struct servtab *sep)
{
if (debug)
warnx(
"enabling %s, fd %d", sep->se_service, sep->se_fd);
#ifdef SANITY_CHECK
if (sep->se_fd < 0) {
syslog(LOG_ERR,
"%s: %s: bad fd", __FUNCTION__, sep->se_service);
exit(EX_SOFTWARE);
}
if (ISMUX(sep)) {
syslog(LOG_ERR,
"%s: %s: is mux", __FUNCTION__, sep->se_service);
exit(EX_SOFTWARE);
}
if (FD_ISSET(sep->se_fd, &allsock)) {
syslog(LOG_ERR,
"%s: %s: not off", __FUNCTION__, sep->se_service);
exit(EX_SOFTWARE);
}
#endif
FD_SET(sep->se_fd, &allsock);
nsock++;
if (sep->se_fd > maxsock)
maxsock = sep->se_fd;
}
void
disable(struct servtab *sep)
{
if (debug)
warnx(
"disabling %s, fd %d", sep->se_service, sep->se_fd);
#ifdef SANITY_CHECK
if (sep->se_fd < 0) {
syslog(LOG_ERR,
"%s: %s: bad fd", __FUNCTION__, sep->se_service);
exit(EX_SOFTWARE);
}
if (ISMUX(sep)) {
syslog(LOG_ERR,
"%s: %s: is mux", __FUNCTION__, sep->se_service);
exit(EX_SOFTWARE);
}
if (!FD_ISSET(sep->se_fd, &allsock)) {
syslog(LOG_ERR,
"%s: %s: not on", __FUNCTION__, sep->se_service);
exit(EX_SOFTWARE);
}
if (nsock == 0) {
syslog(LOG_ERR, "%s: nsock=0", __FUNCTION__);
exit(EX_SOFTWARE);
}
#endif
FD_CLR(sep->se_fd, &allsock);
nsock--;
if (sep->se_fd == maxsock)
maxsock--;
}
FILE *fconfig = NULL;
struct servtab serv;
char line[LINE_MAX];
int
setconfig()
{
if (fconfig != NULL) {
fseek(fconfig, 0L, SEEK_SET);
return (1);
}
fconfig = fopen(CONFIG, "r");
return (fconfig != NULL);
}
void
endconfig()
{
if (fconfig) {
(void) fclose(fconfig);
fconfig = NULL;
}
}
struct servtab *
getconfigent()
{
struct servtab *sep = &serv;
int argc;
char *cp, *arg, *s;
char *versp;
static char TCPMUX_TOKEN[] = "tcpmux/";
#define MUX_LEN (sizeof(TCPMUX_TOKEN)-1)
more:
while ((cp = nextline(fconfig)) && (*cp == '#' || *cp == '\0'))
;
if (cp == NULL)
return ((struct servtab *)0);
/*
* clear the static buffer, since some fields (se_ctrladdr,
* for example) don't get initialized here.
*/
memset((caddr_t)sep, 0, sizeof *sep);
arg = skip(&cp);
if (cp == NULL) {
/* got an empty line containing just blanks/tabs. */
goto more;
}
if (strncmp(arg, TCPMUX_TOKEN, MUX_LEN) == 0) {
char *c = arg + MUX_LEN;
if (*c == '+') {
sep->se_type = MUXPLUS_TYPE;
c++;
} else
sep->se_type = MUX_TYPE;
sep->se_service = newstr(c);
} else {
sep->se_service = newstr(arg);
sep->se_type = NORM_TYPE;
}
arg = sskip(&cp);
if (strcmp(arg, "stream") == 0)
sep->se_socktype = SOCK_STREAM;
else if (strcmp(arg, "dgram") == 0)
sep->se_socktype = SOCK_DGRAM;
else if (strcmp(arg, "rdm") == 0)
sep->se_socktype = SOCK_RDM;
else if (strcmp(arg, "seqpacket") == 0)
sep->se_socktype = SOCK_SEQPACKET;
else if (strcmp(arg, "raw") == 0)
sep->se_socktype = SOCK_RAW;
else
sep->se_socktype = -1;
arg = sskip(&cp);
if (strcmp(arg, "tcp/ttcp") == 0) {
sep->se_type = TTCP_TYPE;
sep->se_proto = newstr("tcp");
} else {
sep->se_proto = newstr(arg);
}
if (strncmp(sep->se_proto, "rpc/", 4) == 0) {
memmove(sep->se_proto, sep->se_proto + 4,
strlen(sep->se_proto) + 1 - 4);
sep->se_rpc = 1;
sep->se_rpc_prog = sep->se_rpc_lowvers =
sep->se_rpc_lowvers = 0;
sep->se_ctrladdr.sin_family = AF_INET;
sep->se_ctrladdr.sin_port = 0;
sep->se_ctrladdr.sin_addr = bind_address;
if ((versp = rindex(sep->se_service, '/'))) {
*versp++ = '\0';
switch (sscanf(versp, "%d-%d",
&sep->se_rpc_lowvers,
&sep->se_rpc_highvers)) {
case 2:
break;
case 1:
sep->se_rpc_highvers =
sep->se_rpc_lowvers;
break;
default:
syslog(LOG_ERR,
"bad RPC version specifier; %s\n",
sep->se_service);
freeconfig(sep);
goto more;
}
}
else {
sep->se_rpc_lowvers =
sep->se_rpc_highvers = 1;
}
}
arg = sskip(&cp);
if (!strncmp(arg, "wait", 4))
sep->se_accept = 0;
else if (!strncmp(arg, "nowait", 6))
sep->se_accept = 1;
else {
syslog(LOG_ERR,
"%s: bad wait/nowait for service %s",
CONFIG, sep->se_service);
goto more;
}
sep->se_maxchild = -1;
sep->se_maxcpm = -1;
if ((s = strchr(arg, '/')) != NULL) {
char *eptr;
u_long val;
val = strtoul(s + 1, &eptr, 10);
if (eptr == s + 1 || val > MAX_MAXCHLD) {
syslog(LOG_ERR,
"%s: bad max-child for service %s",
CONFIG, sep->se_service);
goto more;
}
if (debug)
if (!sep->se_accept && val != 1)
warnx("maxchild=%lu for wait service %s"
" not recommended", val, sep->se_service);
sep->se_maxchild = val;
if (*eptr == '/')
sep->se_maxcpm = strtol(eptr + 1, &eptr, 10);
/*
* explicitly do not check for \0 for future expansion /
* backwards compatibility
*/
}
if (ISMUX(sep)) {
/*
* Silently enforce "nowait" mode for TCPMUX services
* since they don't have an assigned port to listen on.
*/
sep->se_accept = 1;
if (strcmp(sep->se_proto, "tcp")) {
syslog(LOG_ERR,
"%s: bad protocol for tcpmux service %s",
CONFIG, sep->se_service);
goto more;
}
if (sep->se_socktype != SOCK_STREAM) {
syslog(LOG_ERR,
"%s: bad socket type for tcpmux service %s",
CONFIG, sep->se_service);
goto more;
}
}
sep->se_user = newstr(sskip(&cp));
#ifdef LOGIN_CAP
if ((s = strrchr(sep->se_user, '/')) != NULL) {
*s = '\0';
sep->se_class = newstr(s + 1);
} else
sep->se_class = newstr(RESOURCE_RC);
#endif
if ((s = strrchr(sep->se_user, ':')) != NULL) {
*s = '\0';
sep->se_group = newstr(s + 1);
} else
sep->se_group = NULL;
sep->se_server = newstr(sskip(&cp));
if ((sep->se_server_name = rindex(sep->se_server, '/')))
sep->se_server_name++;
if (strcmp(sep->se_server, "internal") == 0) {
struct biltin *bi;
for (bi = biltins; bi->bi_service; bi++)
if ((bi->bi_socktype == sep->se_socktype &&
strcmp(bi->bi_service, sep->se_service) == 0) ||
matchservent(bi->bi_service, sep->se_service,
sep->se_proto))
break;
if (bi->bi_service == 0) {
syslog(LOG_ERR, "internal service %s unknown",
sep->se_service);
goto more;
}
sep->se_accept = 1; /* force accept mode for built-ins */
sep->se_bi = bi;
} else
sep->se_bi = NULL;
if (sep->se_maxcpm < 0)
sep->se_maxcpm = maxcpm;
if (sep->se_maxchild < 0) { /* apply default max-children */
if (sep->se_bi && sep->se_bi->bi_maxchild >= 0)
sep->se_maxchild = sep->se_bi->bi_maxchild;
else if (sep->se_accept)
sep->se_maxchild = maxchild > 0 ? maxchild : 0;
else
sep->se_maxchild = 1;
}
if (sep->se_maxchild) {
sep->se_pids = malloc(sep->se_maxchild * sizeof(*sep->se_pids));
if (sep->se_pids == NULL) {
syslog(LOG_ERR, "Out of memory.");
exit(EX_OSERR);
}
}
argc = 0;
for (arg = skip(&cp); cp; arg = skip(&cp))
if (argc < MAXARGV) {
sep->se_argv[argc++] = newstr(arg);
} else {
syslog(LOG_ERR,
"%s: too many arguments for service %s",
CONFIG, sep->se_service);
goto more;
}
while (argc <= MAXARGV)
sep->se_argv[argc++] = NULL;
return (sep);
}
void
freeconfig(cp)
struct servtab *cp;
{
int i;
if (cp->se_service)
free(cp->se_service);
if (cp->se_proto)
free(cp->se_proto);
if (cp->se_user)
free(cp->se_user);
if (cp->se_group)
free(cp->se_group);
#ifdef LOGIN_CAP
if (cp->se_class)
free(cp->se_class);
#endif
if (cp->se_server)
free(cp->se_server);
if (cp->se_pids)
free(cp->se_pids);
for (i = 0; i < MAXARGV; i++)
if (cp->se_argv[i])
free(cp->se_argv[i]);
}
/*
* Safe skip - if skip returns null, log a syntax error in the
* configuration file and exit.
*/
char *
sskip(cpp)
char **cpp;
{
char *cp;
cp = skip(cpp);
if (cp == NULL) {
syslog(LOG_ERR, "%s: syntax error", CONFIG);
exit(EX_DATAERR);
}
return (cp);
}
char *
skip(cpp)
char **cpp;
{
char *cp = *cpp;
char *start;
char quote = '\0';
again:
while (*cp == ' ' || *cp == '\t')
cp++;
if (*cp == '\0') {
int c;
c = getc(fconfig);
(void) ungetc(c, fconfig);
if (c == ' ' || c == '\t')
if ((cp = nextline(fconfig)))
goto again;
*cpp = (char *)0;
return ((char *)0);
}
if (*cp == '"' || *cp == '\'')
quote = *cp++;
start = cp;
if (quote)
while (*cp && *cp != quote)
cp++;
else
while (*cp && *cp != ' ' && *cp != '\t')
cp++;
if (*cp != '\0')
*cp++ = '\0';
*cpp = cp;
return (start);
}
char *
nextline(fd)
FILE *fd;
{
char *cp;
if (fgets(line, sizeof (line), fd) == NULL)
return ((char *)0);
cp = strchr(line, '\n');
if (cp)
*cp = '\0';
return (line);
}
char *
newstr(cp)
char *cp;
{
if ((cp = strdup(cp ? cp : "")))
return (cp);
syslog(LOG_ERR, "strdup: %m");
exit(EX_OSERR);
}
#ifdef OLD_SETPROCTITLE
void
inetd_setproctitle(a, s)
char *a;
int s;
{
int size;
char *cp;
struct sockaddr_in sin;
char buf[80];
cp = Argv[0];
size = sizeof(sin);
if (getpeername(s, (struct sockaddr *)&sin, &size) == 0)
(void) sprintf(buf, "-%s [%s]", a, inet_ntoa(sin.sin_addr));
else
(void) sprintf(buf, "-%s", a);
strncpy(cp, buf, LastArg - cp);
cp += strlen(cp);
while (cp < LastArg)
*cp++ = ' ';
}
#else
void
inetd_setproctitle(a, s)
char *a;
int s;
{
int size;
struct sockaddr_in sin;
char buf[80];
size = sizeof(sin);
if (getpeername(s, (struct sockaddr *)&sin, &size) == 0)
(void) sprintf(buf, "%s [%s]", a, inet_ntoa(sin.sin_addr));
else
(void) sprintf(buf, "%s", a);
setproctitle("%s", buf);
}
#endif
/*
* Internet services provided internally by inetd:
*/
int check_loop(sin, sep)
struct sockaddr_in *sin;
struct servtab *sep;
{
struct servtab *se2;
for (se2 = servtab; se2; se2 = se2->se_next) {
if (!se2->se_bi || se2->se_socktype != SOCK_DGRAM)
continue;
if (sin->sin_port == se2->se_ctrladdr.sin_port) {
syslog(LOG_WARNING,
"%s/%s:%s/%s loop request REFUSED from %s",
sep->se_service, sep->se_proto,
se2->se_service, se2->se_proto,
inet_ntoa(sin->sin_addr));
return 1;
}
}
return 0;
}
/*
* print_service:
* Dump relevant information to stderr
*/
void
print_service(action, sep)
char *action;
struct servtab *sep;
{
fprintf(stderr,
#ifdef LOGIN_CAP
"%s: %s proto=%s accept=%d max=%d user=%s group=%s class=%s builtin=%p server=%s\n",
#else
"%s: %s proto=%s accept=%d max=%d user=%s group=%s builtin=%p server=%s\n",
#endif
action, sep->se_service, sep->se_proto,
sep->se_accept, sep->se_maxchild, sep->se_user, sep->se_group,
#ifdef LOGIN_CAP
sep->se_class,
#endif
(void *) sep->se_bi, sep->se_server);
}
#define CPMHSIZE 256
#define CPMHMASK (CPMHSIZE-1)
#define CHTGRAN 10
#define CHTSIZE 6
typedef struct CTime {
unsigned long ct_Ticks;
int ct_Count;
} CTime;
typedef struct CHash {
struct in_addr ch_Addr;
time_t ch_LTime;
char *ch_Service;
CTime ch_Times[CHTSIZE];
} CHash;
CHash CHashAry[CPMHSIZE];
int
cpmip(sep, ctrl)
struct servtab *sep;
int ctrl;
{
struct sockaddr_in rsin;
int rsinLen = sizeof(rsin);
int r = 0;
/*
* If getpeername() fails, just let it through (if logging is
* enabled the condition is caught elsewhere)
*/
if (sep->se_maxcpm > 0 &&
getpeername(ctrl, (struct sockaddr *)&rsin, &rsinLen) == 0 ) {
time_t t = time(NULL);
int hv = 0xABC3D20F;
int i;
int cnt = 0;
CHash *chBest = NULL;
unsigned int ticks = t / CHTGRAN;
{
char *p;
int i;
for (i = 0, p = (char *)&rsin.sin_addr;
i < sizeof(rsin.sin_addr);
++i, ++p) {
hv = (hv << 5) ^ (hv >> 23) ^ *p;
}
hv = (hv ^ (hv >> 16));
}
for (i = 0; i < 5; ++i) {
CHash *ch = &CHashAry[(hv + i) & CPMHMASK];
if (rsin.sin_addr.s_addr == ch->ch_Addr.s_addr &&
ch->ch_Service && strcmp(sep->se_service,
ch->ch_Service) == 0) {
chBest = ch;
break;
}
if (chBest == NULL || ch->ch_LTime == 0 ||
ch->ch_LTime < chBest->ch_LTime) {
chBest = ch;
}
}
if (rsin.sin_addr.s_addr != chBest->ch_Addr.s_addr ||
chBest->ch_Service == NULL ||
strcmp(sep->se_service, chBest->ch_Service) != 0) {
chBest->ch_Addr = rsin.sin_addr;
if (chBest->ch_Service)
free(chBest->ch_Service);
chBest->ch_Service = strdup(sep->se_service);
bzero(chBest->ch_Times, sizeof(chBest->ch_Times));
}
chBest->ch_LTime = t;
{
CTime *ct = &chBest->ch_Times[ticks % CHTSIZE];
if (ct->ct_Ticks != ticks) {
ct->ct_Ticks = ticks;
ct->ct_Count = 0;
}
++ct->ct_Count;
}
for (i = 0; i < CHTSIZE; ++i) {
CTime *ct = &chBest->ch_Times[i];
if (ct->ct_Ticks <= ticks &&
ct->ct_Ticks >= ticks - CHTSIZE) {
cnt += ct->ct_Count;
}
}
if (cnt * (CHTSIZE * CHTGRAN) / 60 > sep->se_maxcpm) {
r = -1;
syslog(LOG_ERR,
"%s from %s exceeded counts/min (limit %d/min)",
sep->se_service, inet_ntoa(rsin.sin_addr),
sep->se_maxcpm);
}
}
return(r);
}
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